1371 results about "Nanofiltration" patented technology

The invention discloses a printing and dyeing wastewater zero-discharge treatment process based on low-pressure high-power membrane concentration and salt separation synergy. The wastewater is sequentially subjected to the steps of double-alkali softening pretreatment, organic pollutant treatment, forward osmosis low-pressure high-power concentration treatment, salt separation treatment and evaporative crystallization. Wherein the forward osmosis low-pressure high-power concentration treatment is performed in a partitioned manner along the flow direction, the osmotic pressure difference is gradually increased, the transmembrane pressure difference is gradually decreased, and interface electrochemical buffer and low-frequency gas-liquid disturbance can be set to inhibit concentration polarization and pollution. Carrying out nanofiltration and salt separation on the concentrated solution to obtain two paths of saline water mainly comprising Na2SO4 and NaCl, and respectively carrying out evaporative crystallization on the two paths of saline water; and refluxing and reusing the water produced by the draw solution. According to the process, high-power concentration and stable salt separation are realized under low mechanical pressure, the energy consumption is reduced, the water recovery rate and the crystal purity are improved, and zero discharge of wastewater is realized.

The invention relates to the technical field of water treatment equipment, in particular to a coaxial nested ultrafiltration and nanofiltration integrated water purification device and system.The coaxial nested ultrafiltration and nanofiltration integrated water purification device comprises a main shell, and an annular ultrafiltration treatment area and an inner nanofiltration treatment area are coaxially arranged in the main shell. An energy storage adjusting assembly is arranged in the nanofiltration treatment area and comprises an elastic breathing sleeve coaxially arranged outside the nanofiltration membrane assembly in a sleeving mode. The sleeve elastically expands during filtering, so that the effects of buffering pressure and storing energy are achieved; and turbulent flow convex ribs can be arranged on the inner wall of the sleeve, so that the nanofiltration membrane is physically cleaned when the sleeve retracts. Besides, a backwashing pipeline and a valve are arranged, linkage control is carried out when the control unit detects that expansion of the sleeve exceeds the limit, and ultrafiltration produced water stored on the nanofiltration side is reversely pushed by utilizing pressure energy released by retraction of the sleeve so as to backwash an ultrafiltration membrane. According to the invention, the cooperation of pressure buffering, online cleaning of the nanofiltration membrane and energy storage backwashing of the ultrafiltration membrane is realized, the operation is stable, the efficiency is high, and the energy is saved.

The invention provides an intelligent maintenance cleaning device for nanofiltration membrane pollution control and a method thereof, and solves the problems of low maintenance cleaning efficiency, poor adaptability of cleaning parameters and pollution conditions and frequent chemical cleaning of an existing nanofiltration system. Belongs to the technical field of membrane pollution control. According to the invention, the filtering system, the cleaning system and the intelligent decision-making module are integrally designed, so that the closed-loop control of the whole process of real-time monitoring, pollution identification, intelligent decision-making and automatic cleaning of the running state of the nanofiltration membrane is realized. The cleaning effect gating memory neural network model is used as a membrane pollution prediction model, membrane pollution can be accurately predicted, and key cleaning nodes can be identified. The optimal membrane cleaning parameters are generated by adopting a non-dominated sorting genetic algorithm, the usage amount of chemical agents and the cleaning cost are reduced, and the membrane pollution control effect is improved. The invention is applicable to the field of drinking water treatment.

The invention relates to a bionic strong acid-resistant nanofiltration membrane and a preparation method thereof, and the bionic strong acid-resistant nanofiltration membrane comprises a porous support layer and an active separation layer formed on the surface of the porous support layer, the active separation layer is a polymer network layer formed by carrying out interfacial polymerization reaction on a water-phase solution containing polyamine and an oil-phase solution containing polyacyl chloride on the surface of the porous support layer. The water-phase solution and / or the oil-phase solution also contains a bionic amphiphilic phosphate compound, the bionic amphiphilic phosphate compound participates in interfacial polymerization reaction through an active functional group in a molecular structure of the bionic amphiphilic phosphate compound, and the phosphate structure of the bionic amphiphilic phosphate compound is covalently connected into a skeleton of the polymer network layer. The preparation method has the beneficial effects that the bionic amphiphilic phosphate compound with a hydrophilic phosphate head, a hydrophobic alkyl tail and a reaction site is synthesized, so that the bionic amphiphilic phosphate compound is spontaneously and orderly arranged on a water / oil interface and participates in interfacial polymerization, the film forming uniformity is improved, the pore size distribution is narrowed, and the intelligent response characteristic is given to the film.

The invention belongs to the technical field of membrane separation, and particularly relates to a method for preparing a high-flux hollow fiber nanofiltration membrane based on interfacial polymerization, the obtained membrane and application. The method comprises the following steps: firstly, carrying out pre-adsorption treatment on a polyethersulfone hollow fiber ultrafiltration base membrane through a polyethyleneimine aqueous solution to form a reactive anchoring layer; then sequentially dipping in an aqueous phase solution containing piperazine, sodium phytate and nanoscale cellulose whiskers and an organic phase solution containing trimesoyl chloride and 5-isocyanate isopeptide acyl chloride for interfacial polymerization; and finally, carrying out heat treatment on the obtained primary composite membrane, and completing a gas-phase cross-linking reaction in a glutaraldehyde steam atmosphere. According to the method, the hollow fiber nanofiltration membrane with high flux, high selectivity, excellent chlorine resistance and pollution resistance is successfully prepared through a multi-stage strengthening process, and the hollow fiber nanofiltration membrane is suitable for the fields of drinking water purification, industrial wastewater reuse, material separation and the like.

The invention discloses a preparation method and application of an amino-functionalized graphene quantum dot modified MXene loose nanofiltration membrane. The preparation method comprises the following steps: mixing an MXene nanosheet dispersion liquid with an aminated graphene quantum dot aqueous solution, and preparing an amino functionalized graphene quantum dot / MXene mixed dispersion liquid by adopting a self-assembly method; and filtering and depositing the obtained mixed dispersion liquid on the modified base membrane to obtain the MXene loose nanofiltration membrane. According to the preparation method disclosed by the invention, the zero-dimensional aminated graphene quantum dots are creatively embedded into the MXene nanosheets, so that the MXene loose nanofiltration membrane which is stable in structure and regular in stacking is prepared. The nanofiltration membrane has good separation performance on different dyes and inorganic salts while effectively inhibiting water swelling, is a next-generation separation membrane with high stability and high selectivity, is mild and simple in preparation process, and has a wide application prospect.

The invention belongs to the technical field of membrane separation, and particularly relates to a low-pressure high-flux polyamide / polysulfone hollow fiber composite nanofiltration membrane and a preparation method thereof. The preparation method of the composite nanofiltration membrane comprises the following steps: dissolving sulfonated polysulfone, poly (1-vinyl-3-butylimidazole) bromide and polyvinylpyrrolidone to prepare a spinning solution, and spinning to obtain a base membrane; carrying out hydrophilic modification on the base membrane by using 1, 3-propane sultone; then, an aqueous phase solution containing poly (gamma-glutamic acid) and triethylene tetramine and an organic phase solution containing trimesoyl chloride and 3, 5-diaminobenzoic acid are subjected to interfacial polymerization in the inner cavity of the modified base membrane to form a polyamide separation layer; and finally, carrying out heat treatment to obtain the composite nanofiltration membrane. Through the synergistic effect of zwitterionic ionization of the base membrane and biomacromolecule construction of the separation layer, the mass transfer resistance of water is remarkably reduced, unification of high flux and high selectivity is achieved, and good structural stability is achieved.

The invention discloses a preparation method of deer spleen aminopeptide powder in the field of bioactive substance extraction and functional material compositing, and the performance of the deer spleen aminopeptide powder is improved by compositing a multi-stage functional modified material and deer spleen aminopeptide. The preparation method comprises the following steps: cleaning, homogenizing and crushing fresh deer spleen, extracting with a phosphate buffer solution, adjusting the pH value, carrying out enzymolysis, inactivating enzyme, and treating with an ultrafiltration membrane and a nanofiltration membrane in a specific molecular weight range to obtain a concentrated solution; and mixing the concentrated solution with a multi-stage functional modified material under proper conditions, sterilizing, pre-freezing, and freeze-drying to obtain the deer spleen aminopeptide powder. Wherein the modified material is constructed through quaternization modification, nanopore loading, enzyme inhibitor coupling and targeting ligand modification, and has the functions of charge repulsion, steric hindrance, enzyme inhibition and targeting recognition. The deer spleen aminopeptide powder prepared by the invention has high stability and good bioavailability, and is suitable for functional food or health care products.

The invention discloses a hollow fiber nanofiltration membrane based on interfacial polymerization regulation and a preparation method thereof. The method comprises the following steps: preparing a water phase system and an oil phase system, and sequentially injecting the water phase system and the oil phase system into a hollow fiber ultrafiltration membrane; performing interfacial polymerization reaction on the water phase system and the oil phase system on the surface of the hollow fiber ultrafiltration membrane; and drying to obtain the hollow fiber nanofiltration membrane. By adopting the method, the interception performance and flux of the nanofiltration membrane can be effectively adjusted, and the stability and applicability of the nanofiltration membrane are improved. The nanofiltration membrane is low in water contact angle and high in oil contact angle. Particularly, the surface porosity, the effective aperture, the sodium sulfate retention rate, the sodium chloride retention rate, the flux of sodium sulfate, the flux of sodium chloride and other properties of the nanofiltration membrane can be designed and accurately controlled according to requirements, and the properties of the nanofiltration membrane can be accurately designed and customized by adopting the method disclosed by the invention; the performance of the green and natural modified hollow fiber ultrafiltration membrane is realized, and an innovative solution is provided for high-salt resource recovery.

The invention discloses a polyamide acid-resistant nanofiltration membrane and arsenic removal application thereof in hair dye preparation. According to the amide acid-resistant nanofiltration membrane, a polyamine monomer and trimesoyl chloride are subjected to an interface reaction on an ultrafiltration supporting bottom membrane, and the polyamide acid-resistant nanofiltration membrane containing the Telogen structure is obtained. According to the method for removing the arsenic in the hydroxyethyl diphosphoric acid, a polyamide acid-resistant nanofiltration membrane containing a Troger structure is adopted for at least one time of filtration treatment, the concentration of arsenate in the hydroxyethyl diphosphoric acid after secondary filtration treatment is reduced to 4.60 mg / kg from 480.02 mg / kg, and the arsenic content of the hair dye prepared from the hydroxyethyl diphosphoric acid is smaller than 0.07 mg / kg. According to the polyamide acid-resistant nanofiltration membrane containing the Troger structure, which is obtained by adopting a limited preparation method, the acid resistance is greatly improved, the separation selectivity is higher, arsenic in hydroxyethyl diphosphate can be effectively removed, and the arsenic content in a hair dye is greatly reduced.

The invention relates to a nanofiltration membrane element and a production process thereof, and relates to the technical field of membrane separation, the nanofiltration membrane element comprises a central pipe, a membrane unit piece and a fiber winding layer, the central pipe is provided with a plurality of water inlet holes, the membrane unit piece is wound on the outer side of the central pipe, the fiber winding layer is wound on the outer side of the membrane unit piece, and the membrane unit piece comprises a membrane, water inlet mesh cloth and runner cloth; the runner cloth is divided into two cloth layers in the thickness direction of the runner cloth, and each cloth layer is provided with a filtering area, a glue line area and a side line area. A plurality of supporting lines are clamped between the two cloth layers, the supporting lines are located in the filtering area, all the supporting lines are arranged in the axial direction of the center pipe, the supporting lines extend in the radial direction of the center pipe when the cloth layers are in the spreading state, and one ends of the supporting lines are bonded to the positions, away from the connecting edges, of the glue line area; and a gap between the two cloth layers is communicated with the water inlet hole. The compressive strength of the runner cloth can be improved, so that the water passing amount is increased.

The invention discloses a method for separating an egg white polypeptide chain by adopting a coupling membrane, and particularly relates to the field of egg white polypeptide chains, the method comprises the following steps: S1, mixing fresh egg white with a buffer solution, adjusting the initial acid-base environment and initial temperature of a system, and measuring key basic parameters after dispersion treatment; s3, introducing the pretreated egg white liquid into a first-stage membrane assembly, monitoring separation process parameters, obtaining interception efficiency, dynamically adjusting operation parameters, and enabling permeate liquid to enter a second-stage membrane assembly; s7, monitoring system environment parameters and polypeptide activity, obtaining an activity retention rate, dynamically adjusting supply parameters, and maintaining the polypeptide activity; s8, classifying and collecting products according to molecular weight intervals, evaluating comprehensive separation efficiency, completing separation and verifying product indexes; by constructing an ultrafiltration membrane-nanofiltration membrane-reverse osmosis membrane three-stage coupling separation system and combining a dynamic parameter adjustment mechanism based on interception efficiency, separation selectivity and refined purity, the purity and separation efficiency of a polypeptide product are remarkably improved.

The invention discloses a high-performance Mg < 2 + > / Li < + > separation nanofiltration membrane and a preparation method thereof, the Mg < 2 + > / Li < + > separation nanofiltration membrane is a polymer composite membrane, and is composed of a surface separation layer and a support layer; the surface separation layer is formed by self-assembling a polycation electrolyte and a polyanion electrolyte layer by layer, the supporting layer is formed by ultraviolet grafting of any one or two of sodium polystyrene sulfonate, polymethylacrylic acid 3-sulfonic acid propyl ester potassium salt and polyacrylic acid on the surface of a hydrophobic polymeric membrane, and the surface of the supporting layer is negatively charged. The negative charge amount of the supporting layer is gradually reduced from top to bottom; the whole separation membrane has the characteristics that the upper layer is hydrophilic and the lower layer is hydrophobic. By adjusting the charge density and aperture of the supporting layer, the structure of the surface separation layer is influenced, the charge repulsion effect, aperture screening effect and built-in electric field intensity of the whole membrane are enhanced, and the Mg < 2 + > / Li < + > separation factor is increased. Permeation and rapid transportation of water are promoted by virtue of a hydrophilic upper-layer and hydrophobic lower-layer structure, and the membrane flux is improved; the preparation process is simple, and the used solvent is water, so that the method is green and environment-friendly and has a good application prospect.

The invention discloses a high-flux high-pollution-resistance nanofiltration membrane as well as a preparation method and application thereof. The scheme is realized by constructing a gradient separation layer compounded by modified MOF and polyamide on a porous support layer; the preparation method comprises the following steps: preparing a water phase from modified MOF grafted with carboxylate radical and sulfonate ion recognition groups on the surface, a polyamine monomer and an ion channel regulator, carrying out interfacial polymerization on the water phase and an oil phase containing a fluorine-containing acyl chloride monomer on the surface of a porous support membrane, and carrying out heat treatment and metal ion post-treatment, the modified MOF in gradient distribution in the nanofiltration membrane can specifically adsorb Ca < 2 + >, Mg < 2 + > and other scaling ions, and scale formation is inhibited from the source; the composite structure simultaneously realizes high flux and high selectivity; the retention rate of the membrane to Na2SO4 under 0.6 MPa is greater than or equal to 99.2%, the retention rate of the membrane to NaCl is less than or equal to 15%, the flux of pure water is greater than or equal to 20 L.m <-2 >. H <-1 >. Bar <-1 >, and the flux attenuation rate is less than or equal to 16.7% after the membrane runs in high-hardness, high-COD and high-salinity wastewater for 120 hours; the scheme is particularly suitable for zero-discharge pretreatment of high-salinity wastewater such as solid waste percolate with the TDS of 5-30% and chemical engineering.

The invention discloses a protein / polyphenol composite nanofiltration membrane and application thereof, and belongs to the technical field of protein membrane separation. The nano-filtration membrane is formed by modifying an amyloid-like protein film with the thickness of 50-300 nm and the average pore size of 0.4-1 nm by polyphenol and then adhering the amyloid-like protein film to a porous base material, wherein the amyloid-like protein film is formed by unfolding and self-assembling protein under the action of a modifier. The nanofiltration membrane disclosed by the invention can realize efficient selective separation of Mg < 2 + > / Li < + > in salt lake brine with a high magnesium-lithium ratio, has selective separation capacity on mixed anions Cl <-> / SO4 < 2->, can effectively remove heavy metal ions and perfluoro / polyfluoroalkyl compounds in water, and provides an important basis for developing a sustainable and high-performance next-generation membrane separation technology.

According to the system, a PEM electrolytic hydrogen production subsystem electrolyzes fresh water through renewable energy source electric power to produce high-pressure hydrogen and oxygen, and a first strand of medium-low temperature waste heat is generated; the methanol synthesis subsystem synthesizes a green methanol product and generates a second stream of medium and low temperature waste heat; the nanofiltration-reverse osmosis combined seawater desalination subsystem is connected with the PEM electrolytic hydrogen production subsystem, the nanofiltration-reverse osmosis combined seawater desalination subsystem performs seawater pretreatment, nanofiltration desalination softening and reverse osmosis deep desalination to generate fresh water, and the fresh water is buffered by a fresh water storage tank and then is fed back to the PEM electrolytic hydrogen production subsystem to form a fresh water closed loop; the heat recovery loop is used for preheating a seawater feed entering the nanofiltration-reverse osmosis combined seawater desalination subsystem by using the first medium-low temperature waste heat from the PEM electrolytic hydrogen production subsystem and / or the second medium-low temperature waste heat from the methanol synthesis subsystem, so that the viscosity of the seawater feed is reduced, and the membrane flux is improved or the operation pressure is reduced.

The invention discloses a preparation method of a high-stability photoresponse covalent organic framework membrane and application of the high-stability photoresponse covalent organic framework membrane in selective separation of multiple components. 4-azido azobenzene is prepared by carrying out azido reaction on 4-aminoazobenzene in an acidic aqueous solution, and then a BPTA-TAPB-COF membrane is used as a matrix to prepare the high-stability photoresponse covalent organic framework membrane. 4-azido azobenzene is efficiently grafted to the pore wall of the BPTA-TAPB-COF membrane through a click chemical reaction, the photoresponse covalent organic framework membrane is constructed, and the covalent organic framework membrane can be used for multi-component selective separation and is suitable for multi-component systems with different sizes. The azobenzene group in the pore channel of the prepared Azo-COF membrane is subjected to reversible cis-trans isomerization under the irradiation of ultraviolet / visible light, the response speed is high, and the cycle performance is good; the Azo-COF membrane has good application in the light-operated nanofiltration process, the performance of the Azo-COF membrane is not reduced after the Azo-COF membrane is continuously recycled for 12 days, and the structure of the Azo-COF membrane is kept stable.

The invention discloses an advanced organic wastewater treatment method and treatment device based on an advanced oxidation coupling coagulation denitrification method, and relates to the technical field of landfill leachate treatment, kitchen waste treatment, kitchen garbage treatment and the like, the treatment device comprises a coagulation tank unit, a flocculation tank unit, an air floatation and filter tank unit, an ozone catalysis unit and an activated carbon filter unit which are connected in sequence, the ozone generation unit and the tail gas decomposition unit are connected with the ozone catalysis unit. According to the invention, a traditional nanofiltration membrane advanced treatment process in the industry is replaced by an advanced treatment process of coagulation, flocculation, air floatation, filtration, ozone catalysis and activated carbon filtration, so that the generation of a concentrated solution is avoided; the defect that the biogas yield of an anaerobic digestion system is reduced due to the fact that the sulfate-containing concentrated solution flows back to the anaerobic digestion system of the landfill leachate treatment plant or the kitchen waste treatment plant is overcome, the load of a biogas desulfurization system of the landfill leachate treatment plant and the kitchen waste treatment plant is reduced, and the consumption cost of the concentrated solution is greatly reduced.

The invention provides a two-dimensional layered kaolinite nanofiltration membrane, and a preparation method and application thereof, and the preparation method comprises the following steps: mixing kaolinite powder and an intercalator according to a first solid-to-liquid ratio, heating, stirring, carrying out intercalation reaction completely, and carrying out solid-liquid separation to obtain a solid kaolinite intercalation compound; mixing the kaolinite intercalation compound with water according to a second solid-to-liquid ratio, adjusting the pH value of the mixed solution to 9-13, and carrying out dispersion treatment to obtain a kaolinite nanosheet dispersion liquid; enabling the kaolinite nanosheet dispersion liquid to penetrate through the porous basement membrane, and depositing kaolinite nanosheets in the kaolinite nanosheet dispersion liquid on the porous basement membrane to obtain the two-dimensional layered kaolinite nanofiltration membrane; the operation steps are simple, no complex equipment or a large amount of organic solvent is used, and the method conforms to the concept of green chemistry. The prepared two-dimensional layered kaolinite nanofiltration membrane can be used in various fields of water treatment, organic solvent separation and the like, and has a wide application prospect.

The invention discloses an efficient extraction and compounding method of ergothioneine, and relates to the technical field of ergothioneine preparation, the efficient extraction and compounding method comprises the steps of raw material pretreatment, extraction, purification, compounding and embedding, raw material pretreatment adopts an enzymolysis and chelation synergistic technology, extraction adopts a pH response type aqueous two-phase system and is combined with ultrasonic microwave synergistic enhancement, and the compounding and embedding are carried out. A nanofiltration membrane separation and vacuum freeze drying combined process is adopted for purification, a targeted compounding system is adopted for compounding, and a composite wall material microcapsule embedding technology is adopted for embedding. According to the method, the cell wall structure of the raw material is destroyed and the oxidation of active ingredients is inhibited through an enzymolysis and chelation synergistic pretreatment technology, the ergothioneine distribution behavior is regulated and controlled and the mass transfer process is accelerated by matching with a pH response type aqueous two-phase system and ultrasonic microwave synergistic enhanced extraction, and then a nanofiltration membrane separation and vacuum freeze drying combined purification process is combined; impurities are effectively removed, the activity of components is reserved, and the problems of low extraction rate and insufficient purity of a traditional method are solved.

The invention relates to a selective nanofiltration membrane as well as a preparation method and application thereof. The selective nanofiltration membrane comprises a support layer and a separation layer, the separation layer is obtained through interfacial polymerization of an oil-phase reactant and a water-phase reactant; the water-phase reactant comprises a negatively charged monomer and a positively charged monomer; the positively charged monomer comprises any one or a combination of at least two of polyvinylamine, polyethyleneimine, diethylenetriamine, water-soluble chitosan, quaternized polyethyleneimine, polyallylamine or triethylene tetramine. According to the method, monomers with different charges are added into a water phase, so that the nanofiltration membrane is wholly charged and neutral, the interception of sodium sulfate can be effectively reduced, the interception of antibiotics is increased, and the separation of the antibiotics and inorganic salts can be efficiently promoted.

The invention provides low-molecular-weight tea polysaccharide and a preparation method and application thereof, and belongs to the technical field of tea polysaccharide extraction.The preparation method of the low-molecular-weight tea polysaccharide comprises the following steps that 1, tea powder, compound enzyme and water are mixed to obtain an enzymolysis system, and enzymolysis is conducted to obtain enzymatic hydrolysate; 2) performing ultrasonic-microwave synergistic extraction on the enzymatic hydrolysate, and then boiling and extracting to obtain an extracting solution; (3) inoculating compound microorganisms into the extracting solution, and fermenting to obtain fermentation liquor; 4) performing ultrafiltration and concentration on the fermentation liquor to obtain a tea polysaccharide solution; 5, the tea polysaccharide solution is subjected to affinity membrane chromatography and elution, eluent is subjected to reverse filtration through a nanofiltration membrane, trapped fluid is collected, and the low-molecular-weight tea polysaccharide is obtained.The molecular weight of the low-molecular-weight tea polysaccharide ranges from 2 KDa to 5 KDa, and the low-molecular-weight tea polysaccharide can be more easily absorbed by the human body and has the effect of rapidly and remarkably adjusting blood sugar.

The utility model relates to the technical field of mercerizing machines, in particular to an alkali liquor recycling type mercerizing machine which comprises an alkali leaching pool, an alkali leaching tank arranged at one end in the alkali leaching pool, an alkali removing tank arranged at one end in the alkali leaching pool, a separation block fixedly arranged between the alkali leaching tank and the alkali removing tank, a treatment pool fixedly arranged on the outer wall of the alkali leaching pool, and a cleaning assembly arranged in the treatment pool. Two alkali liquor discharging pipes are fixedly arranged on the treatment pond, one ends of the two alkali liquor discharging pipes are communicated with the alkali leaching tank respectively, the other ends of the two alkali liquor discharging pipes are located at the upper end of the treatment pond respectively, the lower end of the treatment pond is communicated with a suction pipe, the suction pipe is communicated with a plurality of first filters, and alkali-resisting nanofiltration membranes are installed in the first filters; the concentrated water end of the first filter is communicated with a permeable pipe. And impurities, ions, small particles and soluble solids in the alkali liquor are removed, so that the quality of the recycled alkali liquor is improved, the cleanliness of recycling of the alkali liquor is ensured, and the damage of fiber impurities and pollutants to fabrics is reduced.

The invention provides a method for separating and extracting bio-based succinic acid from fermentation liquor, which comprises the following steps: (1) enabling the fermentation liquor to sequentially pass through a ceramic membrane and a nanofiltration membrane, and decoloring to obtain bio-based succinic acid decolored liquor; (2) sequentially carrying out ion exchange impurity removal and concentration treatment on the bio-based succinic acid decoloring solution to obtain a bio-based succinic acid concentrated solution; and (3) carrying out multi-stage cooling crystallization on the bio-based succinic acid concentrated solution to obtain the bio-based succinic acid, the multi-stage cooling crystallization comprises first-stage crystallization, second-stage crystallization and third-stage crystallization which are carried out in sequence. Through the steps of integrated membrane filtration, decoloration, ion exchange, concentration, multi-stage crystallization and the like, thalli, proteins, pigments, inorganic ions and other impurities in fermentation liquor can be efficiently removed, so that a high-purity bio-based succinic acid product is obtained, meanwhile, the product yield is increased, and energy consumption and waste discharge are reduced.

The invention discloses a nicotinic acid immobilized enzyme conversion method, which comprises the following steps: taking wet thalli containing nitrilase, preparing a flocculation clear liquid, passing the flocculation clear liquid through an ultrafiltration membrane, carrying out embedding immobilization to obtain embedded particles not greater than 2mM, and after the embedded particles are hardened, separating and purifying the obtained conversion liquid by adopting a membrane separation method to obtain the nicotinic acid immobilized enzyme. Sequentially carrying out microfiltration, activated carbon decoloration, ultrafiltration, nanofiltration decoloration, acidification crystallization and centrifugation to finally obtain a nicotinic acid finished product. The immobilized enzyme prepared by the method disclosed by the invention can stably exist in nitrile substances, can be repeatedly used for many times, and is high in stability and low in enzyme activity loss rate, and a separated and purified product is free of impurities and high in yield.

The invention discloses an acid-resistant nanofiltration membrane and a preparation method thereof, and belongs to the technical field of membrane separation. The gradient heterojunction active layer is formed on the base film through sequential interfacial polymerization and comprises a polysulfonamide bottom layer adjacent to the base film and a polyamine-metal organic framework composite layer located on the polysulfonamide bottom layer; the gradient heterojunction active layer is coated with the pH response self-repairing layer, and the self-repairing layer comprises pH response type microcapsules dispersed in cross-linked polyvinyl alcohol hydrogel; the membrane has excellent self-repairing capability and maintenance convenience, the repairing efficiency of artificial microcosmic damage in an acid environment within 24 hours can reach 85% or above, tiny scratches and defects generated in the operation or installation process of the membrane can be automatically repaired, the failure of the whole membrane element caused by tiny damage expansion is avoided, and the service life of the membrane element is prolonged. And the unplanned shutdown risk and the special repair and maintenance cost are reduced.

This invention relates to the field of nanofiltration membrane sealing equipment technology, and in particular to a nanofiltration membrane filament sealing device. The nanofiltration membrane includes several filaments with overlapping ends. The sealing device includes: a frame with a feeding port; a clamping mechanism that uses the tension of the overlapping filaments to clamp the filaments; a positioning mechanism for the heat-sealing position of the nanofiltration membrane filaments, the positioning mechanism being arranged on the frame and above the clamping mechanism, the positioning mechanism being used to abut against the curved portion of the nanofiltration membrane filaments; and a heat-sealing mechanism for heat-sealing the ends of the nanofiltration membrane filaments, the heat-sealing mechanism including a heating wire for ironing the ends of the filaments to seal them. Through the design of the clamping mechanism, positioning mechanism, and heat-sealing mechanism, the heat-sealing position of the nanofiltration membrane is confirmed, and the nanofiltration membrane filaments are trimmed while sealing the ends of the nanofiltration membrane filaments.

The invention provides an integrated nanofiltration combination device for high-quality drinking water treatment and a treatment method, and belongs to the technical field of water treatment. The problems of low utilization rate of water resources and high risk of concentrated water discharge in high-quality drinking water treatment of a nanofiltration technology are solved. The nanofiltration combination device comprises a water inlet tank, a nanofiltration module, a concentrated water tank, an ultrasonic disperser, an induced crystallization fluidized bed, a softening agent tank and an antisludging agent tank, the water inlet tank is connected with the nanofiltration module, a treated water outlet of the nanofiltration module is connected with a water outlet pipe, a nanofiltration concentrated water outlet of the nanofiltration module is connected with the concentrated water tank, and the antisludging agent tank is connected with the concentrated water tank. The concentrated water tank is connected with the ultrasonic disperser, the ultrasonic disperser is connected with a water inlet of the induced crystallization fluidized bed, the softening agent gallipot and the scale inhibitor gallipot are respectively connected with the induced crystallization fluidized bed, and a water outlet of the induced crystallization fluidized bed is connected with the water inlet tank. The device is mainly used for high-quality drinking water treatment.

The invention relates to the field of separation and purification, in particular to an anti-pollution nanofiltration membrane for magnesium-lithium separation, the anti-pollution nanofiltration membrane comprises a base membrane and a functional layer, and the functional layer is prepared from the following raw materials in parts by weight: a water phase: 1.5-2.5 parts of piperazine, 0.1-1 part of lauryl sodium sulfate, 0.5-2 parts of glycerol, 1-2 parts of triethylamine, 0.6-2 parts of ionic polymer, and the balance of water for supplementing the total amount of the water phase to 100 parts; the ionic polymer comprises at least one of sulfobetaine metacrylic acid ester, sulfobetaine and carboxyl betaine metacrylic acid ester; and an oil phase: 0.1-1 part of trimesoyl chloride, and the total amount of the oil phase is supplemented to 100 parts by normal hexane or isoparaffin. The ionic polymer is added, and a compact hydration layer is formed on the surface of the membrane by using a betaine group of the ionic polymer, so that the membrane pollution probability is reduced, and common inorganic scaling and organic pollution in the high-salt brine are remarkably inhibited; in addition, the ionic polymer enables the membrane surface to have strong negative electricity, and the magnesium ion rejection rate is improved; and the ionic polymer can also reduce the lithium ion transmission energy barrier and reduce the rejection rate.

The invention discloses a high-temperature-resistant maintenance-free nano dust filtration system and method, and belongs to the technical field of dust filtration systems. The system comprises a dust filtering main body, a nano ceramic filter element assembly, an automatic blowback system and a control system. The nano ceramic filter element is sequentially provided with an outer coarse filter layer, a middle medium filter layer and an inner fine filter layer from outside to inside, so that a radial gradient aperture structure is formed, and graded interception of dust is realized. The automatic blowback system is configured in a way that double electromagnetic pulse valves are connected in series to form double-peak collaborative blowback airflow which is firstly subjected to high-pressure impact stripping and then is subjected to high-flow removal. The control system continuously collects pressure difference data and calculates the pressure difference change rate, the remaining time for reaching a pressure difference threshold value is predicted according to the pressure difference change rate, the back flushing triggering opportunity is judged, self-adaptive dust removal control is achieved, meanwhile, the pressure difference recovery rate before and after back flushing is calculated, and back flushing parameters are automatically adjusted. According to the invention, high-efficiency purification of high-temperature dust-containing gas and long-term maintenance-free operation of the system are realized, and the service life of the filter element is remarkably prolonged.